The invention is directed to an apparatus for individual illumination of objects, comprising a stationarily attached reflector arrangement which reflects incident light rays in a direction onto the objects to be illuminated.
Apparatus of this type are disclosed, for example, by AT Patent 38 66 70 B and by DE 35 34 285 A1. The reflector arrangement is arranged at a prescribed height at an erect rail or at a tower. A light source or a spotlight arrangement for illuminating the reflector arrangement is provided either on the ground or at the tower or at the rail at a prescribed distance below the reflector arrangement. The light from the light source or the spotlight arrangement incident on the reflector arrangement is then emitted by the reflector arrangement in the direction of the objects to be illuminated. Given larger fields to be illuminated, the reflector arrangement is formed of sub-reflectors. Undesired glare phenomena can be avoided by reflector surfaces curved in a suitable way.
As practice has shown, particular manufacturing difficulties result for such reflectors when they are exposed year in and year out to different meteorological conditions and air pollutants, as is the case, for example, given an apron illumination for air fields. In such instances, the mirror layer applied to the reflector surface requires a protective layer that meets high demands and whose transparency properties or the like dare not be deteriorated, even in long-term operation, in order to avoid losses in efficiency. Over and above this, it is necessary that the faultless adhesion between the mirror layer and the protective layer arranged thereabove is also preserved when the reflector arrangement is constantly exposed to great temperature fluctuations.